Secondary

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Original poster: "Ian McLean" <ianmm-at-optusnet-dot-com.au> 

Hi everyone,

Small update on my first coils progress.  I wound my secondary today !  By
hand.  Well ... I did make up a makeshift jig, but I turned the jig by hand,
no power tools  Boy are my hands sore now.

It took about 4 hours ... :-o

I have wound 1,200 turns of 0.63mm enamelled copper onto my 6" thin-walled
PVC form (stormwater pipe).  The form was completely sanded back to a nice
pure white and coated with 4 coats of polyurethane sealer before I started
winding.  I did not bother drying the form first before sanding and sealing
it.  I couldn't fit it in the oven, and as it has been raining here, I was
too impatient to wait for and leave it in the sun for a few days.

The windings are very snug and tight, and it looks really good.  No kinks,
overlaps, or gaps anywhere.  My winding length came out at just over 33
inches.  I am removing about an inch of windings from the top of the form
and space winding the last few turns in that spot.  Final winding length
will be 32".  I wound it all the way snug up to the PVC cap on the pipe (PVC
caps temporarily on both ends to allow bolts for the jig), to ensure the
windings laid nice and straight.  I want to remove the inch from here to
leave about 2 inches free at the top of the form for space winding 1 or 2
turns and toroid spacing.

Just the primary to do now and a topload.

It was a good experience for my first coil, but I don't think I will ever
wind another secondary coil like that again ;)

BTW, I have not sealed the windings yet, so I have wrapped copious amounts
of electrical tape around both ends until tommorrow when I will seal it.  I
am planning on using L.S.E. (Liquid Styrene Epoxy, i.e. fibreglass resin).
If anyone has better suggestions for sealing my windings please let me know.
I am a little concerned about LSE heating up too much during curing and
damaging the enamel on the windings ...

Regards
Ian